An unknown foreign country code appears on your phone. Should you call back? The answer depends on the code, the context, and what you know about the number. Some international dialling codes are regularly exploited by fraudsters to generate revenue through international premium-rate numbers — this is the principle of the one-ring scam, or wangiri. Others correspond to countries with which you have legitimate connections. Here is how to tell the difference.
The one-ring scam (wangiri)
Wangiri (a Japanese term meaning literally "one ring and hang up") is a simple but effective fraud technique. An autodialler calls your number, lets it ring once or twice, then hangs up. Curious — or thinking you missed an important call — you call back. You are then connected to an international premium voice service that charges several euros on connection, plus a prohibitive per-minute rate while you wait or listen to a message.
Most frequently abused country codes
- +222 — Mauritania
- +232 — Sierra Leone
- +269 — Comoros
- +509 — Haiti
- +678 — Vanuatu
- +685 — Samoa
This list is not exhaustive and changes regularly as fraudsters move to new codes once older ones become widely known and routinely blocked.
European codes also exploited
In 2026, scammers increasingly use European-looking VoIP codes to appear more credible: +376 (Andorra), +382 (Montenegro), +389 (North Macedonia). A call from a European country with which you have no connection warrants the same caution as an exotic prefix.
The golden rule
If an international call from an unknown number lasted fewer than five seconds and no voicemail was left, do not call back. A person with a genuine reason to contact you from abroad will leave a voicemail, send an email, or call again. Search the number on TelCheck before engaging, and report incidents to Signal Conso (signalconso.gouv.fr) or directly to ARCEP (arcep.fr). If you have already called back, contact your carrier immediately to dispute any charges incurred.